Just recently (about 2k miles ago) put in a GMPP 350 H.O. crate motor. A friend and I did the swap, both mildly experienced (Him with the most, he put a USED ZZ4 in his 91 RS).

Anyway, about a month ago an old man came by and got my old L03 I put in the paper for 20 bucks and he asked me if I did the cam break in step...I said uhh no and he said you have to run it around 2k-2.5k rpms for a half hour when you first get it running to break in the cam or it will ruin the cam! That got me thinking "Ohh crap ohh crap ohh crap my 2700 dollars and hours of work is ruined."

We also made the mistake of using Mobil 1 5-30w because my girlfriend screwed up and bought the Mobil 1 instead of just Mobil regular and we didn't want to return 5 quarts of oil blah blah. GM also had some small amount of oil already in the engine when they shipped it to us, and we just dumped the Mobil 1 5-30 in and I drove it daily to work and back with no problems and right around the 500 miles mark, I changed the oil and put in Mobil 10-30 regular oil and I've been using that for the past 1k miles.

Recently, I've noticed a ticking noise, sounds like its either coming from the passenger side head (rock slapping the cover) or my Injectors...Other than the ticking noises, the car runs great and has plenty of power (can't wait to get the 3.42s installed to finish the project.) Ohh! Before someone says exhaust leak, i've placed my hand near each port of the headers and felt nothing, no black buildup on the block either. Also tightened down the header bolts twice since they got installed with the new motor. One exhaust leak was from the y-pipe, but replaced those two gaskets and it stopped that noticeable loud ticking.

Can someone address the ticking issue? I'm 99% sure its NOT an exhaust leak. Also - advice on oil change intervals and what to do at this point?

I planned on using the 60degreev6.com change interval with a new engine (normal oil every 2000 miles till 10,000 then switch to Mobil 1 full synthetic, then change the filter every 2,000 till you get to 20,000 then change the oil and filter.) Good idea or not? Guy seems to know what he is talking about.:lala:

 

Flat tappet cams need about 20 min break in at about 2000 rpm. Find out if the crate motors are already broken in before they ship. Probably not but worth looking into.

You may have gotten lucky and the cam had enough lube on it and had sufficient oil to keep it lubricated enough to break in anyway. I think you would have noticed by now if you wiped out a lobe.

As far as the synthetic issue, you probably would just be looking at a longer time for the rings to set. Doubt it did any damage at all.

I know that valve cover is a pain to get to if you still have all the emmisions stuff there but you will have to take it off if you want to eliminate that as the ticking. One of the rockers will be noticebly loose or you will have to run it for a short time and see if one of em is smacking at you.

 

I don't have any emmissions stuff at all. What are the rockers supposed to be torqued at?

Thanks for making me feel better about the break in, it idles decent and runs smooth when you give it gas.

 

There is no torque spec, you set the lash on them. Being that you have hydraulic lifters you tighten them down until the pushrod is making good enough contact between the rocker arm and the lifter that it is not easy to spin. That is just about zero lash. Then you give a half turn to preload the lifter. This is all done when the lifter is on the backside of the lobe. In other words zero lift. Do a search on setting valve lash and you will find the several different methods of determinig when the cam lobe is at zero lift.

Now if one has come loose then something has caused that. It could be something as simple as the nut coming loose but that is highly unlikely. Other things could be a stud coming out, a lobe wore down enough to let it be slightly loose, or even a bad lifter. I'll bet that is not what the problem is though.

But when I said to check it, I just meant to take the valve cover off and see if one is sloppy loose. I say sloppy because it's ok if you can just move it side to side slightly. The lifters can bleed a little and allow that. But see if one feels like you could almost take it off the pushrod. That would be to loose. And if you go ahead and run it without the cover on and listen near it you can hear it noticebly smacking at you. But a little oil will spill out onto the ground.

 

using low viscosity sinthetic and not following the proper breakin procedures is a definate no-no. If your worried that you rolled a lobe then pull the covers and watch the rocker arms. If one arm doesnt seem to be moving as much as the others or not movingmuch at all then your cam wiped out. Worst case senario is that you have to spend 120 some odd dollars on a new cam + lifters and a day or two to install it. Id check the lash first, though. The employees in gms mexico plant do a less then stellar job of setting the lash. On my gmgoodwrench, when i got it, the lash was so tight that the engine would make a 'WHHHOOOSSSHHH' sound and backfire out the tbi when i hit the gas because the exaust and intake vavles where staying open

 

Ok i'll check the rockers to see if they're excessively loose.

About the cam - I haven't noticed any adverse effects, the motor runs great...I'll defintely start the car with the covers off to see if one rocker arm isn't moving.

 

mines ticking too, and reading all of this just worres me more and more that I did somethingw rong with my beautiful new engine.....sounds great and everything, idles fine, and doesn't stumble or anytihng...just ticks a bit.

HOPE everything is fine on yours too!!

 

That is no where near the worst case scenario. If you wiped a lobe, you will need to take down the whole engine. Sure you may not "have" to. YOu may know someone who didnt. But if it was my money riding on it, I sure as hell wouldnt be putting a new cam in, with all the possible particles from that lobe floating around. If the cam is bad, tear it down, and get it thoroughly cleaned. It just isnt worth it not too.

 

WOW this is an old thread.

One of the rockers on the passenger side head was loose. I just tightened them down a few weeks after this thread and the car has been running great since then.

 

Wow almost exactly a year old thread. The funny thing is some of us are still here browsing and responding to it. Glad to here that's all it was.